DieselShip's Online Content Library

Q1. a) How does heat treatment affect the properties of metals? Discuss common heat treatment processes. (6)

b) Describe the factors that influence the corrosion of metals and methods of prevent corrosion. (6)

c) What are the factors that affect the mechanical properties of materials, such as hardness, toughness, and ductility? (4)

Q1.a) Describe the following and explain their function (8)

i) Hawse pipe

ii) Spurling pipe

iii) Cable stopper

iv) Bitter end

b) With the aid of a sketch of a ship bow show the arrangement of anchor cable from anchor to chain locker. (8)

Q1. (a) State FOUR reasons for persistent slackening of holding down bolts of a main engine. (6)

(b) State FOUR precautions to be observed when fitting non-metallic chocks in order to ensure accurate choking. (4)

(c) State the periodic checks to be made in order to assess the effectiveness of an engine chocking system. (6)

Q1. In engine rooms that are operated under UMS conditions describe with the aid of sketches how the following are monitored:

(a) The perforation of a high-pressure fuel pipe (7)

(b) The imminence or possibility of a scavenge fire (7)

(c) Engine room bilges (6)

Q1. (a) Sketch a circuit diagram for an automatic voltage regulator illustrating how the A.V.R. utilizes a silicon-controlled rectifier to control the excitation system for an alternator. (10)

(b) Describe how the A.V.R. monitors output and controls the excitation system. (6)

Q1. The main requirements which a fuel injection system must fulfil are (16)

(a) Accurate metering of small amount of fuel oil

(b) Control of quality of fuel injection

(c) Proper timing of the fuel injection

(d) Selective distribution of the fuel in the combustion space

State whether each one of the points made above are true or false with reasons.

Q2. In the absence of external forces, adding weight to one side of a floating vessel, will cause the vessel to (16)

(a) Heel until the angle of loll is reached.

(b) List until the centre of buoyancy is aligned vertically with the centre of gravity.

(c) Trim to the side opposite TCG until all moments are equal.

(d) Decrease draft at the centre of flotation.

Briefly justify your answer.

Q2. Explain the advantages of fitting highly rated medium speed engines with double exhaust and air inlet valves (6)

(b) State the disadvantages of double valve arrangements (4)

(c) Explain the possible causes of persistent burning of exhaust valves if it is:

(i) General to most cylinders (3)

(ii) Specific to a single cylinder (3)

Q2. With reference to the ISPS Code state the following.

(a) Duties of ship's security officer (8)

(b) Shipping company's responsibilities (6)

(c) Certificate issued as per the code and its validity (6)

Q2. Overcurrent protection relays are built into main alternator breakers to safeguard the individual alternators and the distribution system against certain faults.

(a) Sketch a typical relay. (8)

(b) Describe the operation of the relay sketched in (a) (8)

Q5. A biological sewage system develops a fault, which necessitates opening the unit for repair. Explain the following:

(a) The risk associated with opening the unit. (6)

(b) The precautions taken to reduce the risk. (6)

(c) Explain the significance of biological oxygen demand (B.O.D). (4)

Q2. Make a diagrammatic sketch of an exhaust gas boiler. Describe its construction and explain how it is maintained in an efficient condition (16)

Q3. Work is being carried out in drydock on a large sea water inlet chest and the valves. Describe the inspection you would carry out:

(a) As the work starts (8)

(b) During and after the work. (8)

Q3. (a) Sketch and describe a non-portable 136-liter foam fire extinguisher (8)

(b) Briefly explain how to operate the foam extinguisher (3)

(c) State the two constituents used, which enable stable foam to be produced (3)

(d) State for what approximate length of time, the engine should generate foam (3)

(e) Where on board ship would you expect such an extinguisher to be located (3)

Q3. (a) Sketch and describe a power (watt) meter for an A.C. switchboard. (8)

(b) State why type of load governs power factor and give examples of power factor for a resistance load and for normal marine operation. (8)

Q3. Explain the following briefly with reference to a domestic refrigeration system on board a ship. (16)

(a) Ingress of air into the freon system.

(b) Loss of refrigerant from a condenser.

(c) Water in the freon system.

(d) Icing of condenser external surface.

Q3. a) Draw a labelled sketch of midship section of a double hull oil tanker. (8)

b) What are Aframax, Suezmax, ULCC and VLCC tankers? (8)

Q3. Make a report to the Chief Engineer of your vessel about malfunctioning of low lub oil pressure alarm for the auxiliary engine, observed during your watch, with special emphasis on the possible consequences. (16)

Q4. (a) What is the function of slip rings in an AC motor? (6)

(b) Compare Direct–On-Line (DOL), Star-Delta, and Auto-Transformer methods of motor starting. Which method is preferred and why? (10)

Q4. (a) How are heat exchangers protected from the effects of corrosion? (8)

(b) What are the problems associated with biofouling? (8)

Q4. With reference to an emergency source of electrical power in cargo ships:

(a) Describe a typical power source (10)

(b) Give a typical list of essential services, which must be supplied simultaneously (5)

(c) Explain how the emergency installation can be periodically tested (5)

Q4. (a) Sketch a water-tight door and frame showing manner of attachment to bulkhead and the additional reinforcement carried by the bulkhead to compensate for the aperture (8)

(b) Explain how watertightness of the door and frame mating surface is ensured with an hydrostatic pressure tending to force the laces apart. (4)

(c) Describe the means of remote closing operation of the door and state how many closing stations there are and their position. (4) DONE

Q4. a) What are the advantages of corrugated bulkheads? (6)

b) Sketch and describe a corrugated transverse watertight bulkhead (10)

Q5. Write short notes on the following with details of the system and the purpose with neat sketch, as necessary:

a) Shaft hull grounding system. (8)

b) Rudder grounding system. (8)

Q5. Describe the procedure for the regular maintenance routines to be carried out on the Fixed CO2 fire-fighting system. (16)

Q5. Sketch and explain the construction of a feed Check Valve. Why is it known as double shut off arrangement. (16)

Q5.a) What is free surface effect. (6)

b) Explain the methods used to reduce the free surface effect in ship construction and while operating the ship. (10)

Q1. a) Describe the routine testing required for self-contained breathing apparatus sets. (10)

b) Describe the procedure to be adopted to find missing personnel in a smoke-filled accommodation area. (10)

Q6. A jacket cooling water, plate type cooler for the engine system is stripped open during overhaul for survey purposes, State out a list of components, parts or areas, which you would like to particularly check yourself before the survey. (16)

Q6. (a) Describe, with the aid of a sketch, the braking arrangement for the controlled lowering of lifeboats (10)

(b) State the periodic survey requirements relating to the wire rope fall of lifeboats (10)

Q6. (a) What are the different types of DC motors? (6)

(b) A 10 H.P. 230 V shunt motor takes an armature current of 6A from 230 V mains at no load runs at 1200 r.p.m. The armature resistance is 0.25Ω. Determine speed and electromagnetic torque when the armature takes 36 amps with the same flux. (10)

Q6. with reference to auxiliary boiler water impurity define the effects of the following salts: (16)

(a) Calcium carbonate,

(b) Sodium chloride,

(c) Magnesium chloride,

(d) Calcium sulphate

Explain how the quantity of each is determined and controlled.

Q6. (a) What is the significance of GM-GZ curve. (6)

(b) The pitch of a propeller is measured by means of a batten and cord. The horizontal ordinate is found to be 40 cm while the vertical ordinate 1.15 m at a distance of 2.6 m from the centre of the boss. Calculate the pitch of the propeller and the blade width at that point. (10)

Q7. During the watch main engine crank case mist detector alarm has sounded.

(a) List the steps to be taken to meet this emergency situation. (8)

(b) Subsequent inspection and action required to put the engine on normal operation (8)

Q7. (a) Sketch a simple line diagram showing a shipboard oily water separator in series with a coalescing second stage (8)

(b) Briefly describe the above arrangement and its operations also state the allowable oil content in p.p.m. of the discharge effluent from such an arrangement (8)

(c) Explain how oil density and temperature relate to separation (4)

Q7. An amplifier has an open-circuit voltage gain of 1000, an input resistance of 2000 Ω and an output resistance of 1.0 Ω. Determine the input signal voltage required to produce an output signal current of 0.5A in a 4.0Ω resistor connected across the output terminals. If the amplifier is then used with negative series voltage feedback so that one tenth of the output signal is fed back to the input, determine the input signal voltage to supply the same output signal current. (16)

Q7. Write short notes on the following:

(a) Ultrasonic testing (8)

(b) Shaft earthing device (8)

Q7. (a) Explain why the draught of a ship decreases when it passes from fresh water to seawater and vice versa. (6)

(b) A lock gate which is 15m wide has salt water on one side to a depth of 8m and fresh water on the other side to a depth of 9m. Find the resultant thrust on the lock gate and state on which side of the gate it acts. (10)

Q7. a) With the help of simple diagram, explain Variable Injection Timing (VIT). (8)

b) Explain with suitable diagram, start and end of VIT points. (4)

c) Explain with sketch variation of P(Max) with VIT position. (4)

Q8. With reference to starting air receivers:

(a) Explain why starting air receivers should be drained frequently. (6)

(b) Describe the procedure for the inspection of the internal surfaces of an receiver, indicating the possible defects, which may be encountered. (10)

Q8. (a) What do you understand by Specific Fuel Oil Consumption? Give some examples of SFOC for a two stroke engine and the auxiliary engines. (6)

(b) Explain the terms: (10)

(i) Flash point

(ii) Pour point

(iii) Calorific value

(iv) CCAI value

(v) Octane number and

(vi) Cetane number

Q8. (a) List the SOLAS requirements for steering gear system of an ocean going ship. (10)

(b) Describe the drills and exercises mandated by the SOLAS convention with regards to the steering gear system with reference to the convention. (10)

Q8. (a) Explain how fluorescent tubes power factor is improved. (6)

(b) A fluorescent lamp taking 80W at 0.7 power factor lagging from a 230V, 50-Hz supply is to be corrected to unity power factor. Determine the value of the correcting approach required. (10)

Q8. (a) Sketch a screw displacement pump and explain its operation (10)

(b) State the factors which affect its efficiency. (6)

Q8. (a) Describe the function of the stern frame. (6)

(b) The water plane area of a ship at 8.4 m draught is 1670 m2. The area of successive water planes at 1.40 m intervals below this are 1600,1540, 1420, 1270, 1080 and 690 m2 respectively. Calculate the displacement in fresh water at 8.4 m draught and the draught at which the ship would lie in sea water with the same displacement. (10)

Q9. During recent periods of manoeuvring, a number of air start valve bursting discs or cones have failed. In the circumstance, indicate how the actual cause might be:

(a) Detected (8)

(b) Rectified (8)

Q9. (a) Explain about non-linear resistors with some examples and illustration on how they differ from linear resistor. (6)

(b) A half-wave rectifier is used to supply 50V d.c. to a resistive load of 800Ω. The diode has a resistance of 25 Ω. Calculate a.c. voltage required. (10)

Q7) With reference to main air reservoirs:

(a) Explain with line sketch the manner in which mountings are attached to the shell (6)

(b) Explain why regular internal inspection is advisable (4)

(c) What are the areas that need particular attention during the inspection and survey of a main air reservoir. (6)

Q9. a) Explain why an unstable ship is dangerous. (6)

(b) A vessel travelling at 17 knots turns with a radius of 450 m when the rudder is put hard over. The centre of gravity is 7 m above the keel, the transverse metacentre 7.45 m above the keel and the centre of buoyancy 4 m above the keel. If the centripetal force is assumed to act at the centre of buoyancy, calculate the angle of heel when turning. The rudder force may be ignored. (10)

Q9. Compare the desirable qualities of the lubricating oil selected for each of the following duties:

a) Auxiliary diesel engines. (4)

b) Stern tube bearings. (4)

c) Refrigeration compressors. (4)

d) Gear case of purifier. (4)

Give reasons for the differing properties of the oils recommended for these four purposes.